If you can find someone to sell you a spare release sear, it's easy enough to do yourself. The factory hammer is designed with an extra hook to have the secondary release sear added later, and it's an incredibly simple job, just a little bit of stoning...not like other guns that aren't designed for releases, where significant metal and even wood work must be done. Take your stock off and look at it, and it will be obvious enough how to do...and if you have an older one with the correct (un-waxed) screw in the top of the trigger shoe, you can even convert back and forth between release and pull simply by externally adjusting that sear engagement screw through the hole in the trigger guard.

Boilerplate mumbo-jumbo: I assume absolutely no responsibility for your use of this information. Use caution and good sense. Test extensively on an empty gun before loading a live shell. If you don't feel confident, by all means, send it off and spend the several hundred dollars.